Biologger measurements of feeding in the American lobster <i>Homarus americanus</i> (H. Milne Edwards, 1837) (Decapoda: Astacidea: Nephropidae) in the wild

Abstract American lobsters, Homarus americanus (H. Milne Edwards, 1837), have long been understood to be generalist predators and scavengers, yet little is known about their feeding behavior in the wild. We used custom-built biologgers to directly measure mandibular movements and feeding activity, heart rate, and locomotion of freely moving lobsters in their natural habitat. We recorded 408 discrete feeding bouts during eight deployments yielding nearly 274 hours of data. Lobsters fed throughout the day and night (averaging 1.46 feeding bouts–hour), but most feeding bouts were very short (less than two minutes in length, and involving fewer than 10 bites). As a result, feeding occurred in just over 4% of the total minutes of observation. While the heart rates of lobsters consistently and significantly increased during periods of greater locomotor activity, feeding did not influence heart rate. There was also no correlation between locomotor activity and feeding activity. These data suggest that lobsters are often moving or feeding, but seldom eating large meals for prolonged periods. The determination of whether a lobster is foraging from activity records alone is consequently likely to be challenging.